Pen needle assemblies are well known in the art. To minimize discomfort, pen needle assemblies typically use needles in the range of 29 to 31 gauge. Where a pen injector is used to mix or reconstitute substances into a solution for delivery, thin needles, such as those in the range of 29 to 31 gauge, may be susceptible to clogging by agglomerations which result from re-suspension or incomplete mixing of the substances.